'Game of Thrones': Gemma Whelan Joins Growing Cast

The actress will play the role of Yara Greyjoy, who is known in the books as Asha.

Gemma Whelan is heading to Belfast.

As first reported by EW, the actress has been cast as Theon Greyjoy’s (Alfie Allen) warrior sister Yara Greyjoyon HBO’s Game of Thrones, The Hollywood Reporter has confirmed.

The actress will play the daughter of Balon Greyjoy and his wife, Alannys, described as being fierce and proud and whom defies traditional gender roles by commanding her own ship, the Black Wind.

The character in the George R.R. Martin novel A Song of Ice and Fire was named Asha, but is being changed so as to avoid confusion with another character in the series named Osha.

Whelan’s credits include Gulliver’s Travels and The Wolfman.

Game of Thrones, which began production in Belfast on its second season in July, has continued to bulk up its cast, recently addingStephen Dillane as Stannis Baratheon, the older brother of the late King Robert (Mark Addy); and Carice van Houten as Melisandre, an intimidating woman who councils Stannis in his quest to claim the throne.

Gwendoline Christie was also cast recently as Brienne, Maid of Tarth, as was Natalie Dormer, who will play Margaery Tyrell.